splitkb.com
Firmware - Microcontrollers

Why would I want to socket a microcontroller?

Sockets allow you to remove a microcontroller without having to desolder it.
This page applies to DIY kits only. Preassembled keyboards will already have made this choice for you. The Halcyon Series, for example, feature a socketed microcontroller as well, which allows for it to be reused or replaced when needed, while other preassembled keyboards usually have their controller soldered to the keyboard itself.

Socketing a microcontroller is quite useful. Socketing a component makes it possible to remove it without having to desolder it. For microcontrollers, this proves especially useful, as their many pins make it a very difficult job to desolder without causing damage to either the controller or the keyboard PCB it's mounted to.

You can choose to mount your controller to your keyboard using the pin headers included with the controller. This saves a bit of money, but if you need to replace the controller later in case it is damaged or because you'd like to troubleshoot after building your keyboard, desoldering will prove very difficult. For this reason, we strongly recommend socketing your controller, unless you're confident that you will not have to remove your controller.

In the past, Pro Micro controllers with Micro USB ports were popular. Those ports were rather fragile, so socketing was used as a way to easily replace the controllers. Thankfully, today's controllers tend to use USB C with a far more sturdy connector, so you won't have to worry much about the longevity of your controller's connector.

A set of Mill Max sockets with pins, enough to solder one of the usually two required controllers

A set of Mill Max sockets with pins, enough to solder one of the usually two required controllers.

Socketing options

Socketing your controller requires two parts: the sockets themselves, and the mating pins. For the sockets, we use low profile Mill Max sockets as the only option: they're just that good! For the mating pins, we do have a few alternatives.

  • The most convenient option are Samtec socket headers, where the pins are retained in a plastic housing. This makes them very straightforward to install, and because of how they're installed, the pins are not prone to bending.
  • A popular option are the Mill Max pins, which are a little more affordable, yet plenty sturdy. They do need to be inserted into the sockets one by one, but that's not too big of a deal.
  • You can also opt to use the clipped legs off of diodes, which are included with MX-based Aurora kits or can be ordered separately. They are rather fragile, but when installed with care, they'll work for at least one removal, which is usually good enough for the cost.

Questions? Help us improve!
Do you have questions after reading the documentation? Do you have feedback about this page, or about the documentation in general? Please send us an email. You can use the buttons below which will open your mail client or app with a template, or send your mail to support@splitkb.com.